Height Adjustable Chair Armrest

ABSTRACT

A height adjustable chair armrest has a lower tube, an upper tube, and a push member. Two circular supporting units are provided on upper and lower ends of the lower tube so that the lower tube has an exact contact with the upper tube and a smooth adjustment can be achieved. A flexible gripper secured to one side of the upper tube receives urgently a fastener provided on one side of the push member so that pressing the push member will make a first protrusion at a lower section of the push member to depart from one of a plurality of holes of the lower tube so as to adjust the height of the armrest. Meanwhile, a protrusion protrudes from an inner side of the upper tube for cooperating with a bar groove extending vertically on the lower tube to provide a smooth guide of movement of the upper tube.

FIELD OF THE INVENTION

The present invention relates to a height adjustment structure for achair armrest and more particularly a height adjustable armreststructure positioned on both sides of a chair, which is easy to bemanufactured and fast to be assembled with stability and accuracy.

BACKGROUND OF THE INVENTION

There are many models developed and designed by industry for adjustingheight of chair armrests. In general, there are provided upper and lowertubes combined together. One of the tubes has a control groove forallowing an elastic lifter assembly to move up-and-down. The other tubeis provided with said elastic lifter assembly for adjusting directionand height of the chair armrest. Therefore, a user can adjust thearmrest at a desired position and height in accordance with the mostcomfort.

SUMMARY OF THE INVENTION

In order to overcome the shortages of the conventional height adjustablechair armrest structure which is currently developed by the industry,the present invention is to provide another improved height adjustablearmrest structure for a chair. More particularly, the chair armreststructure of the present invention can be individually manufactured andis easy to be assembled. Further, the chair armrest can keep a stableposition while the height adjustment is performed.

In one object of the present invention is to provide a chair armreststructure including an upper and lower tubes and a push member. The pushmember is mounted on one side of the upper tube. Pressing of an uppersection of the push member will make a first protrusion at a lowersection of the push member to depart from one of a plurality of holes ofthe lower tube so as to adjust the height of the armrest by simpleoperation, and releasing of the upper section of the push member willmake the upper section of the push member to return to the originalposition by expansion of an elastic element and cause the firstprotrusion at the lower section of the push member to enter into one ofthe holes of the lower tube at the related position.

In another object of the present invention is that each of upper andlower ends of the lower tube is formed with a circular groove having twospaced holes for allowing a circular supporting unit having an openingto be mounted thereon; and each end of the circular supporting unitdefining the opening have an inward protrusion respectively for beinginserted into the hole of the circular grooves of the lower tube so thatthe lower tube has an exact contact with the upper tube and a smoothmovement of the upper tube is achieved when the height adjustment of thearmrest is performed.

In yet another object of the present invention is to provide a bargroove extending vertically on one side of the lower tube between upperand lower circular grooves for receiving a protrusion protruding fromone inner side of the upper tube to provide a smooth guide of movementand a highest and lowest limit of height adjustment when the heightadjustment of the armrest is performed.

In yet another object of the present invention is to provide a convexmember with a containing space formed on a middle section on one side ofthe upper tube for receiving a flexible gripper. The gripper is bent toform a gripping space having a narrower opening for allowing a fastenerprovided on one side of the push member with a wider outer section and anarrower inner section to be fitted therein so that the push member hasa flexible and stable contact with the upper tube.

In yet another object of the present invention is to provide arestriction part having an annular groove on one side of the upper tubecorresponding to the push member for holding the elastic element bycooperating with a second protrusion on a recess of said push member soas to provide a stable and elastic operation of the push member.

In yet another object of the present invention is to provide a throughhole on one end of the upper tube for allowing the first protrusion ofthe push member to movably pass therethrough and for being coordinatedwith the plurality of the holes of the lower tube.

In yet another object of the present invention is to provide a framearound the convex member, the restriction part and the through hole forallowing the push member to be mounted thereon and to be flexiblypushable.

The above and other objects, features and advantages of the presentinvention will become apparent from the following detailed descriptiontaken with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective exploded view showing a height adjustable chairarmrest according to the present invention;

FIG. 2 is a side cross-sectional view showing the assembled armrest ofFIG. 1;

FIG. 3 is a cross-sectional view taken along line 30-30 of FIG. 2;

FIG. 4 illustrates a height adjustment of the chair armrest according tothe present invention;

FIG. 5 is another perspective exploded view showing the chair armrestaccording to the present invention; and

FIG. 6 is a view of a partial assembled chair armrest according to thepresent invention.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

The foregoing aspects, as well as many of the attendant advantages andfeatures of this invention will become more apparent by reference to thefollowing detailed description, when taken in conjunction with theaccompanying drawings.

The present invention relates to a height adjustable chair armrest.Referring to FIG. 1, the chair armrest structure comprises a lower tube1, two circular supporting units 2, an upper tube 3, a flexible gripper4, a push member 5, an elastic element 6, and a pad 7.

The lower tube 1 is made of plastic with a predetermined thickness and alower section of the lower tube 1 is covered by an L-shaped metalsupporting unit 11. The inner side of the lower tube 1 has a bar groove12 extending vertically. A plurality of holes 13 arranged in the rangeof the length of the bar groove 12 is provided at one side of the lowertube 1 adjacent the bar groove. Each of the upper and lower ends of thelower tube 1 is formed with a circular groove 14. Each of the circulargrooves 14 is provided with two spaced holes 15 on the same side as thebar groove 12.

Each of the circular supporting units 2 has an opening 21 and is shapedin accordance with the shape of the circular grooves 14 of the lowertube 1. The thickness of each circular supporting unit 2 is larger thanthe width of each circular groove 14 so that the circular supportingunits 2 project slightly over the lower tube 1. Each end of each of thecircular supporting units 2 defining the opening 21 have an inwardprotrusion 22 respectively for being inserted into one of thecorresponding holes 15 of each circular groove 14 of the lower tube 1.

The movable upper tube 3 has an interior space 31 having a shapedepending on the profile of the lower tube 1. A protrusion 32 protrudesfrom one sidewall of the interior space 31 of the upper tube 3 (in thisembodiment, the protrusion 32 has a cross sectional shape of a triangle)for cooperating with the bar groove 12 of the lower tube 1 to provide asmooth guide of movement and a highest and lowest limit of heightadjustment. A frame 33 is provided along one side of the upper tube 3. Amiddle section of the frame 33 is formed with a containing space 35defined by a convex member 34. An upper section of the frame 33 isprovided with a restriction part 36 having an annular groove 37, and alower end of the frame 33 has a through hole 38. Further, a horizontalsupporting unit 39 is mounted on the top of the upper tube 3.

The flexible gripper 4 has a bending section having a gripping space 41which is shaped depending on the shape of the convex member 34 of theframe 33 of the upper tube 3. The flexible gripper 4 can be made offlexible material and the gripping space 41 has a narrower opening.Therefore, wings 42 on both sides of the gripper 4 can be secured to theconvex member 34 by screwing elements 43 when the bending section of thegripper 4 is inserted into the containing space 35 of the upper tube 3.

The push member 5 is shaped depending on the profile of the frame 33 ofthe upper tube 3 for controlling the height adjustment of the armrest.At the middle section of the push member 5, there is provided with afastener 51 having a wider outer section and a narrower inner sectionfor being urgently received in the gripping space 41 of the gripper 4. Arecess 52 having a protrusion 53 is provided at an upper section of aninner side of the push member 5. Both ends of the elastic element 6 arerespectively against the protrusion 53 and the annular groove 37 of therestriction part 36 of the upper tube 3. A protrusion 54 is provided ona lower section of the inner side of the push member 5 for passingthrough the through hole 38 of the frame 33 of the upper tube 3 and oneof the holes 13 of the lower tube 1 at the related position in sequence.

The pad 7 is combined with the horizontal supporting unit 39 of theupper tube 3 for providing support and comfort for resting an arm.

In assembly, please refer to FIG. 2. FIG. 2 shows that the circularsupporting units 2 are respectively mounted on the circular grooves 14of the lower tube 1. The protrusions 22 of each of the circularsupporting units 2 are inserted into the holes 15 of each of thecircular grooves 14, as shown in FIG. 3. Further, the upper tube 3 ismounted on the lower tube 1, and the protrusion 32 in the interior space31 is urgently pushed downwardly into the bar groove 12 of the lowertube 1 for up-and-down movement. The circular supporting units 2combined with the lower tube 1 have a stable contact with sidewalls ofthe interior space 31 of the upper tube 3. The bending section of thegripper 4 is inserted into the containing space 35 of the upper tube 3and both wings 42 of the gripper 4 are positioned on the convex member34 by screwing elements 43. Further, one end of the elastic element 6 issecurely laid on the protrusion 53 of the push member 5. The fastener 51at the middle section of the push member 5 is urgently inserted into theconcave gripping space 41 of the gripper 4 of the upper tube 3. Theother end of the elastic element 6 is laid against the annular groove 37of the upper tube 3. In the meantime, the protrusion 54 at the lowersection of the push member 5 passes through the through hole 38 of theupper tube 3 and one of the holes 13 of the lower tube 1 at the relatedposition in sequence. Finally, the pad 7 is stably secured with thehorizontal supporting unit 39 of the upper tube 3 by screws 71 so as tofinish the high adjustable chair armrest simply and easily.

In operation, please refer to FIG. 4. The upper section (as indicated byan arrow) of the push member 5 is pressed. The fastener 51 at the middlesection of the push member 5 then acts as a pivot so that the protrusion54 at the lower section of the push member 5 departs from the hole 13 ofthe lower tube 1 due to compression of the elastic element 6. Therefore,a user can adjust the upper tube 3 of the armrest at a desired height.After the desired height is reached, the upper section of the pushmember 5 is released and returns to the original position by expansionof the elastic element 6. The protrusion 54 at the lower section of thepush member 5 will enter into one of the holes 13 of the lower tube 1 atthe related position. Therefore, the height and position of the chairarmrest is maintained.

An upper end of the vertical bar groove 12 of the lower tube 1 can havea shape as shown in FIGS. 5 and 6, to prevent the protrusion 32 out ofthe limit defined by the bar groove 12 when the upper tube 3 is pulledupwardly as adjustment. Thus, a receiving groove 16 is formed on anupper end of the bar groove 12 of the lower tube 1, to allow aprotrusion 32′ in the interior space 31 of the upper tube 3 (in thisembodiment, the protrusion 32′ has a cross sectional shape of rectangle)to be smoothly pushed into the bar groove 12 through the receivinggroove 16. Then, a block 17 formed as the shape of the receiving groove16 is received in the receiving groove 16 and fastened by screwing ascrew element 18 through holes 171 and 161. As a result, the protrusion32′ is movable reliably between the bar groove 12.

While the invention has been particularly shown and described withreference to the preferred embodiments thereof, these are, of course,merely examples to help clarify the invention and are not intended tolimit the invention. It will be understood by those skilled in the artthat various changes, modifications, and alterations in form and detailsmay be made therein without departing from the spirit and scope of theinvention, as set forth in the following claims.

1. A height adjustable chair armrest, comprising a lower tube, an uppertube mounted on the lower tube, and a push member; wherein: the pushmember is mounted on one side of the upper tube, pressing of an uppersection of the push member will make a first protrusion at a lowersection of the push member to depart from one of a plurality of holes ofthe lower tube by compression of an elastic member so as to adjust theheight of the armrest by simple operation, and releasing of the uppersection of the push member will make the upper section of the pushmember to return to the original position by expansion of the elasticelement and cause the first protrusion at the lower section of the pushmember to enter into one of the holes of the lower tube at the relatedposition.
 2. The height adjustable chair armrest according to claim 1,wherein a convex member with a containing space is formed on a middlesection on one side of the upper tube for receiving a flexible gripper;and said gripper is bent to form a gripping space having a narroweropening for allowing a fastener provided on one side of the push memberwith a wider outer section and a narrower inner section to be fittedtherein so that the push member has a flexible and stable contact withthe upper tube.
 3. The height adjustable chair armrest according toclaim 1, wherein a restriction part having an annular groove is providedon one side of the upper tube corresponding to the push member forholding the elastic element by cooperating with a second protrusion on arecess of said push member so as to provide a stable and elasticoperation for the push member.
 4. The height adjustable chair armrestaccording to claim 1, wherein a through hole is provided on one end ofthe upper tube for allowing the first protrusion of the push member tomovably pass therethrough and for being coordinated with the pluralityof the holes of the lower tube.
 5. The height adjustable chair armrestaccording to claim 1, wherein the upper tube is provided with a convexmember with a containing space for receiving a flexible gripper, arestriction part on an upper end for allowing the elastic element to bestably positioned, a through hole on a lower end for allowing the firstprotrusion of the push member to movably pass therethrough, and a framearound the convex member, the restriction part and the through hole forallowing the push member to be mounted thereon and to be flexiblypushable.
 6. A height adjustable chair armrest, comprising a lower tube,an upper tube mounted on the lower tube, and a push member; wherein:each of upper and lower ends of the lower tube is formed with a circulargroove having two spaced holes for allowing a circular supporting unithaving an opening to be mounted thereon; and each end of each circularsupporting unit defining the opening has an inward protrusionrespectively for being inserted into one of the holes of each circulargroove of the lower tube so that the lower tube has an exact contactwith the upper tube and a smooth movement of the upper tube is achievedwhen the height adjustment of the armrest is performed.
 7. A heightadjustable chair armrest, comprising a lower tube, an upper tube mountedon the lower tube, and a push member; wherein: a bar groove extendsvertically on one side of the lower tube between upper and lowercircular grooves for receiving a protrusion protruding from one innerside of the upper tube to provide a smooth guide of movement and ahighest and lowest limit of height adjustment when the height adjustmentof the armrest is performed.
 8. The height adjustable chair armrestaccording to claim 7, wherein an upper end of the bar groove of thelower tube is formed with a receiving groove to allow a protrusioninside the upper tube to be smoothly pushed into the bar groove throughthe receiving groove, and a block is then fastened in the receivinggroove so that the protrusion is reliably movable between the bargroove.